<style>
.new{
  border:2px solid green;
  background:lightgreen;
  padding:10px;
}
</style>
<script type="text/javascript" src="js/jquery-1.8.2.min.js"></script>
<script type="text/javascript">
  $(document).ready(function(){
    
    $('.addClass').click(function(){
      $('p').addClass('new');
    });
    $('.removeClass').click(function(){
      $('p').removeClass('new');
    });
  });
</script>
<h4 class="addClass">Add Class</h4>
<h4 class="removeClass">Remove Class</h4>
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